C1115
ABS Power Relay Output Short Circuit To Battery
Chassis Chassis/Safety ABS Electrical 🔴 Serious — Stop or limit driving
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What This Actually Means
In plain language — no jargon

The ABS system's power relay is stuck energized, continuously sending battery voltage when it should be off—like a light switch that won't turn off. This causes electrical stress and can drain the battery or damage the ABS control module.

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Symptoms You May Notice
3 known symptoms for this code
ABS warning light illuminated on dashboard
Battery drains quickly when vehicle is parked
ABS system non-functional or erratic braking behavior
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Embedded Systems Insight
What the ECU/ECM is actually computing

The ABS module monitors the relay output voltage to ground, expecting it to drop to near 0V when de-energized and rise to battery voltage when energized per system demand. A short to battery means the relay output remains at battery voltage continuously, regardless of module commands.

Voltage & Parameter Thresholds

Parameter Normal Range Fault Condition
Relay Output Voltage (De-energized) 0.2-0.5V 10-14V (battery voltage)
Current Draw (Idle) 0.5-2A >5A continuous
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Diagnostic & DIY Fix Guide
Check these in order — from cheapest to most complex
1
ABS Power Relay
Locate the relay in the engine bay fuse/relay box and swap with an identical unit to test; if fault clears, replace permanently.
2
Wiring harness to relay
Inspect relay connector pins and output wire for corrosion, melting, or pinched insulation causing a short.
3
ABS Control Module
If relay and wiring are clean, the module's internal output transistor may be shorted; requires module replacement or reprogramming.